System and method for marking an ophthalmic lens

Abstract

A system and method for providing a discernable marking within a contact lens including forming a marking section substantially simultaneously with the formation of a bulk section of said lens. The marking section may be formed entirely during formation of the bulk section or may include preformed elements and may be extruded, inlaid, embedded, injected, or dyed within the bulk section. The bulk section may be formed as a rod, a sheet, or as an injection molded lens. The marking section extends substantially from the front to back surfaces of the lens.

1 . An opthalmic lens having a marking formed therein wherein said lens comprises:
 a bulk section; and   a marking section visually distinct from said bulk section, said marking section extending substantially from a front surface of said lens to a rear surface of said lens.   
     
     
         2 . The lens of  claim 1 , wherein said bulk section comprises a first polymer composition and said marking section is produced by at least one of extruding, inlaying, and embedding a second polymer composition within said bulk section. 
     
     
         3 . The lens of  claim 1 , wherein said marking section comprises at least one of a colorant, opacity gradient, and a reflective agent. 
     
     
         4 . The lens of  claim 3 , wherein said marking section is formed from a polymer having substantially the same base composition as said bulk portion. 
     
     
         5 . The lens of  claim 1 , where said marking section comprises a preformed ribbon encapsulated by said bulk section during extrusion of said bulk section. 
     
     
         6 . The lens of  claim 1 , wherein said marking section is substantially co-extensive with the thickness of an adjacent portion of said bulk section. 
     
     
         7 . The lens of  claim 1 , wherein said marking section of a first lens exhibits a first visual characteristic indicative of one of a left eye lens or a right eye lens. 
     
     
         8 . The lens of  claim 7 , wherein said marking section of a second lens exhibits a second visual characteristic different from said first visual characteristic to indicate the other one of said left eye lens and said right eye lens. 
     
     
         9 . The lens of  claim 1 , wherein said marking section comprises a visual characteristic distinguishable from said bulk section when not placed on an eye and not distinguishable to the wearer when placed on an eye. 
     
     
         10 . A method of forming polymeric stock for use in producing an opthalmic lens having a discernable marking formed therein, the method comprising the steps of:
 extruding a bulk section of a polymeric stock, said polymeric stock comprising one of a rod and a sheet; and   producing a marking section within said polymeric stock visually distinct from said bulk section and extending substantially the finished thickness of said lens.   
     
     
         11 . The method of  claim 10 , wherein said marking section is produced by at least one of extruding, inlaying, and embedding of said marking section within said bulk section. 
     
     
         12 . The method of  claim 11 , wherein said marking section is formed from a polymer having substantially the same base composition as said bulk portion. 
     
     
         13 . The method of  claim 10 , where said marking section comprises one of a preformed ribbon and a preformed plug introduced into said polymeric stock during extrusion of said bulk section. 
     
     
         14 . The method of  claim 10 , wherein said marking section comprises at least one of a colorant, an opacity gradient, and a reflective agent. 
     
     
         15 . The method of  claim 10 , wherein said marking section is substantially co-extensive with an adjacent portion of said bulk section prior to formation of said lens. 
     
     
         16 . The method of  claim 10 , wherein said marking section of a first lens exhibits a first visual characteristic indicative of one of a left eye lens and a right eye lens. 
     
     
         17 . The method of  claim 16 , wherein said marking section of a second lens exhibits a second visual characteristic different from said first visual characteristic to indicate the other one of said left eye lens and said right eye lens. 
     
     
         18 . The method of  claim 10 , wherein said marking section is formed in advance of said bulk section and is crosslinked thereto during extrusion of said bulk section. 
     
     
         19 . The method of  claim 10 , wherein said marking section is located at the periphery of said lens. 
     
     
         20 . A method of forming a discernable mark within a contact lens, said method comprising:
 injecting a first polymer composition into a lens mold; and   forming a marking section within said lens, said second polymer composition exhibiting different visual characteristics from said first polymer composition in said lens.   
     
     
         21 . The method of  claim 20 , wherein said marking section extends substantially the thickness of said lens. 
     
     
         22 . The method of  claim 21 , wherein said second polymer composition comprises at least one of a colorant, an opacity gradient, and a reflective agent. 
     
     
         23 . The method of  claim 21 , wherein forming said marking section comprising injecting a second polymer composition into said lens mold. 
     
     
         24 . The method of  claim 21 , wherein forming said marking section comprises disposing a preformed section within said mold. 
     
     
         25 . The method of  claim 21 , wherein said preformed section is positioned is said mold prior to said injecting.